Background and Aims: The ability to recognize past events is a fundamental aspect of our ability to remember. Two processes are thought to underlie recognition memory: recollection and familiarity. Recollection is the process that allows for the retrieval of distinct features associated with the context in which the event was originally encountered. Familiarity is the process that allows for the global assessment of the strength of the memory trace of the event, in the absence of memory for contextual features. A developmental dissociation between the two processes has been documented in behavioral research: Whereas recollection appears to continue to develop over the course of childhood and adolescence, familiarity appears to become relatively stable during childhood. Cognitive neuroscience research with adults has shown that recollection and familiarity rely on distinct brain structures and that activity in these brain regions is dissociable both at time of encoding and at time of retrieval. One gap in our knowledge concerns the neural mechanisms underlying the developmental dissociation between recollection and familiarity. The proposed research aims to address this gap by examining encoding-related processes during development. The specific aims of the proposed project are: (1) to identify the neural correlates of the development of recollection, and (2) to identify the neural correlates of the development of familiarity. Methods: The proposed research involves an event-related functional magnetic resonance imaging (fMRI) experiment with 8-, 10-, 14-, and 18-years-olds (20 participants per age group). Participants will be scanned during an incidental encoding task. Memory for the items processed in the scanner will be tested later, and measures of brain activity will be extracted as a function of this later memory performance. Significance: The proposed research will generate new knowledge about age-differences in the neural substrates of recollection and familiarity related to encoding processes. The findings will contribute to the development of a more comprehensive theory of recognition memory, as well as to an understanding of the relation between brain functioning and cognitive development. Relevance for public health: Knowledge about typical memory development is critical to understanding atypical memory development, as seen, for example, in child populations with traumatic brain injury or type-1 diabetes. Understanding the neural correlates of the development of various learning mechanisms is relevant to facilitating adaptive functioning in a wide range of domains. [unreadable] [unreadable] [unreadable]